Method of welding aluminum



June 16, 1925.

S. A. WILTSIE METHOD OF WELDING ALUMINUM Filed Nov. 11. 1922 Patented June 16, 1925.

UNITED STATES PATENT OFFICE. v

SPENCER A. WILTSIE, OF ERIE, PENNSYLVANIA, ASSIGNOR '10 WELDA WARE PROD- UCTS COMPANY, OF ERIE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

METHOD OF WELDING ALUMINUM.

Application filed November 11, 1922. Serial No. 600,894.

T all whom it may concern: Be it known that I, SPENCER A. Wnrrsm, a citizen of the United States, residing at Erie, in the county of Erie and State of Pennsylvania, have invented'new and useful Improvements in the Methods of Welding Aluminum, of which the following is a specification.

Aluminum has heretofore been welded. The usual practice has been to heat the body of metal to be welded to a temperature just below the welding temperature and then apply an acetylene torch to bring the metal to the welding point. The difliculty with this practice is that the reliminary heating softens the body of the a uminum and is thus objectionable. With my method I apply the preliminary heating locally. If it is a small weld the heat may extend over the entire weld and the metal is then brought up to the welding temperature by progressively heating the joint. If, however, the weld is extended over anything more than a local area I prefer to give to the metal a preliminary heat confined locally to the area of the wel and to advance the area of preliminary heating as the heat for welding is advanced along the loint. This may be accomplished by app ying the prehminary heat to the opposite wall from that to which the welding heat is applied. In this way the areas of heat may e advanced together and a welding temperature may be brought about locally so rapidly as to preclude the extended diffusion of heat and thus the injurious softening of the metal may beprev'ented. To accomplish this with aluminum the manner of producing the preliminary heat at one side of the weld may be any convenient source such as an electric element, an electric are, or a gas flame so long as the heat is controlled by s acing the are or element to a temperature elow that injurious to the aluminum. On the operating side of the weld, however, an acetylene torch or a source of. heat that can be controlled must be, used as the electric arc cannot be controlled directly at the metal to affect a weld of aluminum. f

In the accompanying drawing I have illustratedjtheimanner of practicingthe process. Fig. 1 illustrates the process using an are as a medium for the preliminary heat.

narily. for small welds and while it may be Fig. 2 a view illustrating the utilization of an electric heating element for this purose.

Fig. 3 illustrates a method of using a gas flame for this pur ose. I

1 marks one of tiie walls to be heated, and 2 the other wall. As shown this is the wall of an ordinary kettle, the wall 2 bein the conventional spout. In the method us in Fig. 1 a support 3 is applied to the inner portion of the wall of the receptacle. This support has an opening 3 which exposes the inner surface ofthe wall opposite the point of the weld. Electrodes 5 are ar: ranged to produce an are 4 in position to heat the wall in a local area directly at the weld. The are found most satisfactory is produced by about one hundred'ten or over volt current and the arc is maintained from one-half to three-fourths of an inch from the metal. The metal is given a preliminary heat by the arc of approximately eight hundred degrees Fahrenheit, this temperature giving to the surface a frosted appearance.

{an oxy-acetylene torch 7 producing a slightcarbonizing flame 8 is directed to the joint irectly opposite the point heated by the are. This Intense flame brings the metal in a local area to the weldin temperature and the weld is accomplish so ra idly as to preclude a wide expansion or ifiusion of the heat incident to the weld and thus a minimum of injurious effect of the heat on the metal. As the work is advanced the arc is advanced to correspond to the advancing of the welding flame so that the metal heated in bringing about the weld is confined to a portion of the wall immediately adjacent to the weld. If care is taken this may be confined to a small fraction ofan inch and, therefore, the walls of the finished article as a whole have their original (finality.

In Fig. 2 I illustrate the met 0d usin a heating element 9. In this the insulating material 10 forms the sup 'o'rt for the metal surrounding the weld. is is used ordiadvancedthe preliminary heating where this is used may be' so local as not to require it. InFi 3 a am part 11 is used. This is ordinari y in the orm .of a perforated plate.

Agas burner 12 delivers a flame 13 against the supporting'plate 111. Here ifthenweld is of any extent the gas flame giving the of the material opposite to that subjectedto the preliminary heat whereby the temperature necessary for the weld and which is injurious to the metal is so rapidly applied at the weld as to prevent ext-ended diffusion and injury to the metal away from the weld.

2. The method of welding aluminum which consists in heating the body of the metal locally adjacent to the weld from a source of heat delivered to one side of the material, then raising the temperature of the metal thus preliminarily heated in a local area to a welding temperature with a gas flame directed to the weld from the side of the material opposite to that subjected to the preliminary heat, and then advancing the areas of heat along the weld to advance the weld whereby the temperature necessary for the weld and which is injurious to the metal is so rapidly applied at the weld as to prevent extended diffusion and injury to the metal away from the weld.

8. The method of welding aluminum which consists in subjecting the body of the metal locally adjacent to the weld to a pre liminary heat slightly below the welding temperature by means of an electric arc, and

.'raising the metal with a gas flame in a small area after the preliminary heat to a welding heat, the are being delivered to one side of the body of the metal and the welding heat to the opposing side.

4. The method of welding aluminum which consists in subjecting the body of the metal locally adjacent to the weld to a preliminary heat slightly below the welding temperature by means of an electric arc, and raising the metal with a gas flame in a small area after the preliminary heat to a welding heat, the are being delivered to one side of the body of the metal and the welding heat to the opposing side, said heating areas being advanced to extend the weld.

In testimony whereof I have hereunto set my hand.

SPENCER A. TVILTSIE. 

